The invention relates to a two-stroke internal combustion engine with a piston having a crosshead movable therewith and a connecting rod extending between the crosshead and the crankshaft of the engine, the crosshead being guided for linear movement with the piston.
A two-stroke internal combustion engine of this type is already known (KSZ 90/160 of MAN) from DE-B "Gestaltung und Hauptabmessungen der Verbrennungskraftmaschine (Design and Principal Dimensions of the Internal-Combustion Engine), Harald Maass, Springer Verlag 1979, page 214, Figure 5.62". The engine shown therein has an engine block with a crankcase and with a cylinder housing having a cylinder, in which a piston acts on a crankshaft via a crosshead rod, a crosshead together with crosshead guide and a connecting rod. Arranged between the crankcase and cylinder housing is a partition wall which comprises a sleeve projecting from the crankcase into the cylinder, so that in the bottom dead-center region of the piston, the piston skirt extends partially into the space between the outer contour of the sleeve and the inner contour of the cylinder.
For general background, attention is also drawn to the publications German Patent Specification 3,327,225 and German Offenlegungsschrift 3,206,152.
One disadvantage of internal combustion engines of this type is the complicated design of the engine block with its slits (inlet and outlet slits) and channels (inlet and outlet channel).
Furthermore, known engine blocks which are provided with undercuts for the channels are produced by casting utilizing sand cores and they are subsequently machined at least at the top edges of the slits (control function for gas exchange). A disadvantage of this is the high costs of subsequent machining and the restricted access for chip-removing tools to the slit top edges located inside the cylinder. Moreover, a further disadvantage in the production of engine blocks of this type is to be seen in that the sand cores have to be prepared anew for each new casting.
It is the principal object of the present invention to provide an engine block of an internal combustion engine of the general type in such a way that its production is substantially simpler and more cost-effective in comparison with the hitherto known state of the art.